1. Field of the Invention
This invention relates to a film-forming polymer. More particularly, it relates to a polymer useful for a permselective membrane.
2. Description of the Prior Art
As the materials for producing permselective membranes, there have been known heretofore, several polymers for example, polydimethylsiloxanes and copolymers thereof with polycarbonates or others (U.S. Pat. Nos. 3,980,456, and 3,874,986; and Japan Patent Lay-open No. 26504/1981); as well as olefine polymers such as poly 4-methylpentene-1 (Japan Patent Lay-open No. 4203/1982). However, these polymers can not fulfill all the fundamental requirements, for use as permselective membranes, namely good permeability and selectivity as well as processability to form thin film.